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Publication numberUS5452759 A
Publication typeGrant
Application numberUS 08/119,813
Publication dateSep 26, 1995
Filing dateSep 10, 1993
Priority dateSep 10, 1993
Fee statusPaid
Also published asUS5409060
Publication number08119813, 119813, US 5452759 A, US 5452759A, US-A-5452759, US5452759 A, US5452759A
InventorsThurman B. Carter, Mark W. Schnitker
Original AssigneeWeatherford U.S., Inc.
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Whipstock system
US 5452759 A
Abstract
The present invention, in one embodiment, discloses a whipstock system having an orientation device; a flexion member releasably secured to the orientation device; co-acting lower and upper body members, the lower body member interconnected with the flexion member; a connecting bar which connects the upper and lower body members permitting the upper body member to move downwardly with respect to the lower body member while preventing separation of the two body members; and a concave member secured to and above the upper body member. In one preferred embodiment, one or more movable pawls on the connecting bar move to engage surfaces on one or both body members to prevent upward movement of the upper body member with respect to the lower body member, or conversely movement of the lower body member downwardly away from the upper body member; and movement of the one or more pawls in contact with both body members also forces the two body members apart further stabilizing the system in a tubular. Also disclosed is a setting or installation tool with a mandrel rotatable in an upper housing, the mandrel secured to a lower housing, so that torque or torsion is not transmitted through the tool. Also disclosed is a toggling connection member which permits a concave member to be pushed and then to move upwardly to pivot to a desired position.
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Claims(15)
What is claimed is:
1. A Whipstock system for insertion through a first tubular into a second tubular and for setting within the second tubular, the first tubular having a smaller diameter than the second tubular and the first tubular disposed within a portion of the second tubular, the second tubular having an interior surface, the whipstock system comprising
a lower body member,
an upper body member,
interconnecting means for movably interconnecting the lower body member and the upper body member so that upon application of a downward force on the upper body member the upper body member moves downwardly in the second tubular effecting sideways movement of the lower body member so the lower body member contacts the interior surface of the second tubular thereby wedging the lower body member and the upper body member in place within the second tubular, and
a concave whipstock member secured to or formed integrally of the upper body member.
2. The whipstock system of claim 1 comprising also
the interconnecting means comprising
a connecting bar disposed partially in a first connecting bar groove in the lower body member and partially in a second connecting bar groove in the upper body member, and
the connecting bar grooves and the connecting bar configured so that the connecting bar is movably held in the connecting bar grooves.
3. The whipstock system of claim 2 comprising also
at least one pawl member having opposed pawl member ends and movably mounted on the connecting bar, and movable in response to an upward force on the upper body member so that one of the opposed pawl member ends contacts the lower body member and the other pawl member end contacts the upper body member forcing the two body members apart.
4. The whipstock system of claim 3 wherein the opposed ends of the at least one pawl are toothed to engage their respective body members.
5. The whipstock of claim 2 comprising also
a series of pawls, each pawl having a first toothed end and a second toothed end and movably mounted in a slot on the connecting bar, the pawls movable in response to an upward force on the connecting bar so that the pawls' first ends engage the upper body member and the pawls' second ends engage the lower body member, forcing the two body members further apart and preventing relative movement therebetween.
6. The whipstock system of claim 1 comprising also
at least one toothed slip on an exterior surface of the lower body member for engaging the interior surface of the second tubular.
7. The whipstock system of claim 1 comprising also
orientation means connected to the lower body member for co-acting with an anchor member disposed in the second tubular, the orientation means for correctly orienting the whipstock system with respect to the anchor member.
8. The whipstock system of claim 7 comprising also
flexing means interconnected between the lower body member and the orientation means for facilitating sideways movement of the lower body member in response to downward force applied on the upper body member.
9. The whipstock system of claim 8 comprising also
the flexing means comprising a flexing member with a neck area at which the flexing member flexes in response to sideways force on the lower body member.
10. The whipstock system of claim 8 comprising also
the flexing means comprising
a tube interconnected between the lower body member and the orientation means, the tube having at least one notch therein for facilitating flexing of the tube.
11. The whipstock system of claim 1 comprising also an installation tool, releasably secured to and above the concave member, the installation tool comprising
an upper housing,
a mandrel held rotatably within the upper housing,
a lower housing, the mandrel secured to the lower housing and the lower housing securable to and above the concave member so that rotation of the upper housing does not rotate the concave member and so that the concave member is rotatable without rotating the upper housing, and so that a tensile or compressive force applied to the upper housing is transmitted to the concave member.
12. The whipstock system of claim 11 wherein the installation tool further comprises
a thrust bearing between an upper end of the mandrel and the upper housing, and
the lower housing having a shoulder for abutting the concave member, and
a shear screw for releasably securing the concave member to the lower housing, the shear screw passing through a lower extending portion of the lower housing and into the concave member so that a force directed downwardly on the lower housing is transmitted through the shoulder to the concave member and not through the shear screw, and an upward force on the lower housing is transmitted to the shear screw.
13. The whipstock system of claim 1 wherein the upper body member is connected to the concave member in a toggling connection, the toggling connection comprising
the concave member having a top end and a bottom end and a slot therethrough and a recess below the slot, the recess having a recess opening at the bottom end of the concave member, the slot having a top edge and a bottom edge and the recess opening having a top edge,
the upper body member movably connected to the concave member and having a first hole therethrough and a second hole therethrough,
the upper body member's top end disposed within the concave member's bottom end with the concave member's slot aligned with the upper body member's first hole and a first pin securing the concave member and upper body member together, the first pin extending through the slot and through the first hole of the upper body member, the first pin movable in the slot,
a second pin passing through the recess opening of the concave member and through the second hole of the upper body member,
the concave member and upper body member initially connected so that a force on the concave member directed toward the upper body member urges the top edge of the slot against the first pin and the top edge of the recess against the second pin thereby transmitting the force to the upper body member, and a force on the concave member pulling it away from the upper body member effecting abutment of the first pin against the bottom edge of the slot and movement of the second pin out of the recess, permitting the concave member to pivot about the first pin.
14. The whipstock system of claim 13 wherein the toggling connection further comprises
a shear pin extending into and between the concave member and the upper body member and preventing relative movement therebetween until sufficient force is applied to the connection to shear the shear pin.
15. A whipstock system for insertion through a first tubular into a second tubular and for setting within the second tubular, the first tubular having a smaller diameter than the second tubular and the first tubular disposed within a portion of the second tubular, the second tubular having an interior surface, the whipstock system comprising
a lower body member,
an upper body member,
interconnecting means for movably interconnecting the lower body member and the upper body member so that upon application of a downward force on the upper body member the upper body member moves downwardly in the second tubular effecting sideways movement of the lower body member so the lower body member contacts the interior surface of the second tubular thereby wedging the lower body member and the upper body member in place within the second tubular, the interconnecting means comprising a connecting bar disposed partially in a first connecting bar groove in the lower body member and partially in a second connecting bar groove in the upper body member, and the connecting bar grooves and the connecting bar configured so that the connecting bar is movably held in the connecting bar grooves, a series of pawls, each pawl having a first toothed end and a second toothed end and movably mounted in a slot on the connecting bar, the pawls movable in response to an upward force on the connecting bar so that the pawls' first ends engage the upper body member and the pawls' second ends engage the lower body member, forcing the two body members further apart and preventing relative movement therebetween,
a concave whipstock member releasably secured to the upper body member,
orientation means connected to the lower body member for co-acting with an anchor member disposed in the second tubular, the orientation means for correctly orienting the whipstock system with respect to the anchor member,
flexing means interconnected between the lower body member and the orientation means for facilitating sideways movement of the lower body member in response to downward force applied on the upper body member,
an installation tool releasably secured to the concave member, the installation tool comprising an upper housing, a mandrel held rotatably within the upper housing, a lower housing, the mandrel secured to the lower housing and the lower housing secured to the concave member so that rotation of the upper housing does not rotate the concave member and so that the concave member is rotatable without rotating the upper housing, and so that a tensile or compressive force applied to the upper housing is transmitted to the concave member, and
a toggling connection of the concave member and the upper body member, the toggling connection comprising the concave member having a top end and a bottom end and a slot therethrough and a recess below the slot, the recess having a recess opening at the bottom end of the concave member, the slot having a top edge and a bottom edge and the recess opening having a top edge, the upper body member movably connected to the concave member and having a first hole therethrough and a second hole therethrough, the upper body member's top end disposed within the concave member's bottom end with the concave member's slot aligned with the upper body member's first hole and a first pin securing the two members together, the first pin pushing through the slot and through the first hole of the upper body member, the first pin movable in the slot, a second pin passing through the recess opening of the concave member and through the second hole of the upper body member, the two members initially connected so that a force on the concave member directed toward the upper body member urges the top edge of the slot against the first pin and the top edge of the recess against the second pin thereby transmitting the force to the upper body member, and a force on the concave member pulling it away from the upper body member effects abutment of the first pin against the bottom edge of the slot and movement of the second pin out of the recess, permitting the concave member to pivot about the first pin.
Description
BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention is related to: whipstocks and associated apparatus for use in wellbores; whipstocks insertable through one tubular into another, e.g. through a smaller diameter tubing into a larger diameter casing; whipstock installation tools; whipstock apparatus which can be set by pulling upwardly thereon; and to anchoring apparatus for use in tubulars.

2. Description of Related Art

A variety of "through tubing" whipstocks and tools insertable through tubing are available in the prior art; e.g. the devices disclosed in U.S. Pat. Nos. 5,222,554; 5,211,715; 5,195,591; and 4,491,178.

There is a need for an effective whipstock and associated apparatus which is insertable through a smaller diameter tubular, such as tubing, and then disposable in a larger diameter tubular, such as casing, below the smaller diameter tubular. There is a need for such devices which effectively anchor and correctly orient themselves in the larger diameter tubular.

SUMMARY OF THE PRESENT INVENTION

The present invention, in one embodiment, discloses a whipstock system having an orientation device; a flexion member releasably secured to the orientation device; co-acting lower and upper body members, the lower body member interconnected with the flexion member; a connecting bar which connects the upper and lower body members permitting the upper body member to move downwardly with respect to the lower body member while preventing separation of the two body members; and a concave member secured to and above the upper body member. In one preferred embodiment, one or more movable pawls on the connecting bar move to engage surfaces on one or both body members to prevent upward movement of the upper body member with respect to the lower body member, or conversely movement of the lower body member downwardly away from the upper body member; and movement of the one or more pawls in contact with both body members also forces the two body members apart further stabilizing the system in a tubular.

In one embodiment of such apparatus, movement of the lower body member sideways up against a casing wall for frictional engagement therewith is facilitated by the use of a notched tube connected between the lower body member and the flexion member. The flexion member itself further facilitates such movement of the lower body member since it, preferably, has a reduced area neck which enhances flexing of the flexion member. To enhance frictional contact of the lower body member with the casing, one or more friction members or pads, or toothed slip members can be provided on the exterior of the lower body member which move to contact and frictionally engage the casing's interior surface as the lower body member moves against the casing. One or more toothed members or toothed slips may be used and teeth on different members or slips may be oriented differently; e.g. on one slip teeth may be oriented downwardly to prevent downward movement of the device and on another slip teeth may be oriented upwardly to engage e.g. a casing to prevent upward movement. Initially the total effective largest dimension of the two body members is sufficiently small that they are insertable through a tubular (e.g. tubing) of a relatively small diameter. Then as they move apart with respect to each other the total effective largest dimension of the two body members increases so that one or both engage the interior of a relatively larger diameter tubular (e.g. casing) in which the smaller diameter tubular is positioned.

In one embodiment the connecting bar has an I-shaped cross-section and the upper and lower body members each have a groove with a corresponding shape for receiving part of the connecting bar. Thus the connecting bar prevents the two body members from separating or rotating with respect to each other while at the same time allowing the upper body member to move downwardly adjacent the lower body member permitting the two to move sideways to a controlled extent with respect to each other. Preferably the upper and lower body members are disposed at an angle to each other and the connecting bar is configured and the associated body member grooves are disposed so that as the upper body member moves downwardly with respect to the lower body member, the lower body member contacts and frictionally engages one interior side of the casing and the upper body member moves to contact the other side of the casing's interior; thus stabilizing the apparatus in place. At this point an upward force may be applied to the apparatus, causing the pawls to lock the lower and upper body members together, preferably pushing them slightly farther apart to further stabilize them in place and setting the whipstock in place at the desired location. Further pulling frees any upper setting tool or installation tool, leaving the whipstock correctly positioned.

Appropriate orienting devices are used so that the concave member is correctly oriented with respect to the wellbore to direct a milling tool in a desired direction. Correct orientation of the whipstock system with respect to an anchor in the casing is facilitated in certain preferred embodiments by an installation tool secured to the top of the concave member. The installation tool has a mandrel secured to the concave member, the mandrel rotatable within an upper housing which is itself secured to an upper sub which is threadedly connected to the tool string from which the whipstock is suspended. Preferably the installation tool does not transmit torque to apparatus below it due to the mandrel's rotation. The orienting device at the bottom of the whipstock system may include a scooped receptacle which rotates to correctly orient with respect to and to engage an anchor disposed in the casing.

In one embodiment friction reducing members, substances, or pads may be used on the upper body member to reduce friction between it and the casing so that the upper body member may move downwardly to force the lower body member against the casing's interior and to enhance engagement of a toothed slip or slips on the lower body member with the casing's interior.

In other embodiments, the present invention discloses a whipstock system having: a lower inflatable packer with an orientation key; a stinger assembly with a slot for the key for coacting with the packer to orient the system; stabilizing springs on the stinger assembly; linking apparatus for pivotably linking the stinger assembly to a lower body member; the lower body member preferably with one or more friction members such as a slip with a toothed surface; a wedge slide member movably secured partially within the lower body member and partially within an upper body member; an upper body member shear-pinned to the lower body member so that upon shearing of one or more pins, forcing the upper body member downwardly with respect to the lower body member and forcing the lower body member outwardly, the movement of the two body members constrained and guided by the wedge slide so that the lower body member moves sideways to contact an interior surface of casing in which the system is disposed while the upper body member moves to contact an opposing interior casing surface; the linking apparatus permitting pivoting of the lower body member so it moves sideways; and a whipstock concave member secured to the upper body member, preferably secured pivotably so that concave member lays back against the casing interior at a desired angle to effect a desired milling point and direction. A setting tool is secured to the concave member by a shear stud. In effect the overall largest dimension of the system at the interface of the upper and lower bodies increases as the two move with respect to each other. Thus the system is initially of a first smaller dimension so it is insertable through a relatively small diameter tubular (such as tubing) into a larger diameter tubular (e.g. casing) which extends downwardly beyond the smaller diameter tubular. Then, upon movement of the two body members with respect to each other the effective largest dimension at the body members increases and the body members, by frictional contact with the interior of a relatively larger diameter tubular (e.g. casing in which tubing is disposed), anchor the system with the larger diameter tubular for use therein. The above-described upper and lower bodies and associated interconnecting apparatus, wedge slide, or connecting bar with pawl(s), may be used to anchor any member or device in any tubular or wellbore. Also, friction members such as pads of friction materials and/or toothed slips with teeth pointed upwardly and/or toothed slips with teeth pointing downwardly may be used on both or either body members. Alternatively friction reducing members, devices, or substances may be used on the upper body member to facilitate its downward movement.

In another embodiment of a whipstock system according to the present invention which is similar to that described immediately above, there is no wedge slide member. Interconnecting apparatus such as a linking member (or members) is used to pivotably link a concave member to a lower body member so that downward force on the concave member results in the movement of both the lower body member and the concave member to contact the casing wall. The lower body member pivots with respect to the stinger assembly and moves sideways to frictionally engage one interior side of the casing while the concave member has a bottom portion that pivots with respect to the lower body member and moves sideways (away from the lower body member) to contact the opposite interior side of the casing.

It is, therefore, an object of at least certain preferred embodiments of the present invention to provide:

New, useful, unique, efficient, non-obvious whipstocks and devices for installing them in tubulars;

Such devices for insertion through a smaller diameter tubular in a larger diameter tubular; in one aspect, for insertion through tubing into casing extending below the tubing;

Such devices for effective anchoring of a whipstock in a tubular; and, in one aspect, a whipstock apparatus settable by pulling upwardly thereon;

Such devices for correct orientation of a whipstock with respect to an anchor disposed in casing below tubing therein;

New useful, unique, efficient, non-obvious anchoring devices for anchoring a member or device in a tubular or in a wellbore; and

New useful, unique, efficient, non-obvious setting or installation tools for whipstock orientation which permit relative rotation of a whipstock system and items above the whipstock system in a tool string or tubular string and which, preferably, do not transmit torque; and

New, useful, unique, efficient, non-obvious toggling connections for connecting two members.

Certain embodiments of this invention are not limited to any particular individual feature disclosed here, but include combinations of them distinguished from the prior art in their structures and functions. Features of the invention have been broadly described so that the detailed descriptions that follow may be better understood, and in order that the contributions of this invention to the arts may be better appreciated. There are, of course, additional aspects of the invention described below and which may be included in the subject matter of the claims to this invention. Those skilled in the art who have the benefit of this invention, its teachings, and suggestions will appreciate that the conceptions of this disclosure may be used as a creative basis for designing other structures, methods and systems for carrying out and practicing the present invention. The claims of this invention should be read to include any legally equivalent devices or methods which do not depart from the spirit and scope of the present invention.

The present invention recognizes and addresses the previously-mentioned problems and needs and provides a solution to those problems and a satisfactory meeting of those needs in its various possible embodiments and equivalents thereof. To one of skill in this art who has the benefits of this invention's realizations, teachings, disclosures, and suggestions, other purposes and advantages will be appreciated from the following description of preferred embodiments, given for the purpose of disclosure, when taken in conjunction with the accompanying drawings. The detail in these descriptions is not intended to thwart this patent's object to claim this invention no matter how others may later disguise it by variations in form or additions of further improvements.

DESCRIPTION OF THE DRAWINGS

A more particular description of embodiments of the invention briefly summarized above may be had by references to the embodiments which are shown in the drawings which form a part of this specification. These drawings illustrate certain preferred embodiments and are not to be used to improperly limit the scope of the invention which may have other equally effective or legally equivalent embodiments.

FIG. 1 is a side cross-sectional view of a whipstock system according to the present invention.

FIG. 2 is a side cross-sectional view of part of the system of FIG. 1 including a splined flexion member.

FIG. 3 is a side cross-sectional view of a connecting bar of the system of FIG. 1.

FIG. 4 is a side cross-sectional view of an installation tool of the system of FIG. 1.

FIG. 5A is a side cross-sectional view of a receptacle of the system of FIG. 1. FIG. 5B is a front view of the receptacle of FIG. 5A.

FIG. 6A is a cross-sectional view through the notch of the tube of FIG. 6B. FIG. 6B is a side cross-sectional view of the tube of the system of FIG. 1. .

FIG. 7 is a is a side cross-sectional view of the adapter of the system of FIG. 1.

FIG. 8 is a side cross-sectional view of the splined flexion member of the system of FIG. 1.

FIG. 9A is a side view of a connecting bar of the system of FIG. 1. FIG. 9B is another side view of the connecting bar of FIG. 9A. FIG. 9C is a cross-sectional view of the bar of FIG. 9A.

FIG. 10A is a perspective view of a friction member of the system of FIG. 1. FIG. 10B is a top view of the friction member of FIG. 10A.

FIG. 11A is a side view of an upper body member of the system of FIG. 1. FIG. 11B is another side view of the upper body member of FIG. 11A. FIG. 11C is another side view of the upper body member of FIG. 11A. FIG. 11D is a cross-sectional view along line D--D of FIG. 11B. FIG. 11E is a bottom end view of the upper body member of FIG. 11B. FIG. 11F is a cross-sectional view along line F--F of FIG. 11B.

FIG. 12A is a side view of a lower body member of the system of FIG. 1. FIG. 12B is another side view of the member of FIG. 12A. FIG. 12C is another side view of the member of FIG. 12A. FIG. 12D is a cross-sectional view along line A--A of FIG. 12B. FIG. 12E is a cross-sectional view along line B--B of FIG. 12B. FIG. 12F is a cross-sectional view along line C--C of FIG. 12B.

FIG. 13A is a cross-sectional view along line G--G of FIG. 3 with the connecting bar omitted.

FIG. 13B is a cross-sectional view of the tool of FIG. 3 with upper and lower body members in contact with a casing's interior.

FIGS. 14A-14C is a side schematic views of a system according to the present invention. FIG. 14D is a cross-sectional view along line H--H of FIG. 14A.

FIG. 15 is a side schematic view of a system according to the present invention.

FIG. 16 is a partial side view of a toggling connection according to the present invention.

DESCRIPTION OF EMBODIMENTS PREFERRED AT THE TIME OF FILING FOR THIS PATENT

Referring now to FIG. 1, a whipstock system 10 according to the present invention has a lower receptacle 12 to which is secured a splined flexion member 14 by set screws 32. A locking nut 30 secures a top end of the splined flexion member 14 to an adapter 28. The adapter 28 is welded to a tube 16 which itself is welded to a lower end of a lower body member 18. A connecting bar 15 interconnects the lower body member 18 and an upper body member 20. A concave member 22 is secured to a top of the upper body member 20. An installation tool 24 is releasably secured to a top of the concave member 22.

As shown in FIG. 1, the system 10 has been inserted on a string S which typically includes (from the installation tool up) a crossover sub, a drill collar (for weight), a connector to the drill collar, and a length of coiled tubing which extends to the surface. The tubing T extends through casing C and the casing C extends downwardly below the tubing T. The receptacle 12 has a key slot 34 for receiving a key 36 on a lower anchor member 26 previously emplaced in the casing C, thus correctly orienting the system 10 in a desired orientation with respect to the casing C and therefore with respect to a wellbore (not shown) in which the casing is installed.

Sideways movement of the lower body member 18 is permitted and facilitated by two items: the splined flexion member 14 and the notched tube 16 so that the lower body member will move sideways as desired up against an interior side wall of the casing C. The splined flexion member 14 has a neck 38 of reduced size as compared to the size of a body 40 of the member 14. The splined flexion member 14 (in one embodiment made from steel) flexes at the neck 38. The tube 16 has one (or more) notches 42 cut therethrough which permit the tube 16 to bend to a small degree. As shown in FIG. 6A the notch 42 occupies half of the circumference of the tube 16. Four centralizing bow springs 44 (three shown in FIG. 1) are disposed on the tube 16.

FIG. 4 illustrates the installation tool 24 according to the present invention. The tool 24 has a lower adapter 52 with a sleeve 54 and a block 56. The block 56 is secured to the concave member 22 with a screw 55. A mandrel 58 is threadedly engaged within the sleeve 54 and a set screw 57 prevents rotation of the mandrel 58 in the sleeve 54. The mandrel 58 is rotatable within a housing 62. The housing 62 threadedly engages an upper sub 64. The upper sub 64 interconnects the system 10 to connectors and to connectors and to tubing extending from the surface and into the casing. The mandrel 58 has a flange 66 which abuts an interior shoulder 68 of the housing 62. Brass sleeve bearings 72 facilitate rotation of the mandrel 58. A thrust bearing 74 serves to facilitate rotation of the mandrel 58 with respect to the sub 64 when downward force is applied to the sub 64. The screw 55 does not experience a downward force when the system is being run into the hole since the bottom surface of the sleeve 54 abuts a top surface of the concave. When the screw 55 shears (after the tool is set and the system above the installation tool is to be removed) the shoulder 68 is pulled up against the flange 66 to remove the installation tool 24 from the hole.

FIGS. 5A and 5B show the receptacle 12. It has a key slot 34 for receiving the key 36 on the anchor 26. Material and debris entering a channel 78 exit through ports 82. Set screws 32 hold the receptacle 12 on a lower end of the splined flexion member 14.

As shown in FIGS. 7 and 8, external splines 86 on a top end of the splined flexion member 14 mate with internal spline recesses 88 in the adapter 28. The splined flexion member 14 (or alternatively the adapter 28) can be rotated to achieve a desired orientation of the receptacle 12 with respect to the adapter 28 and hence with respect to the rest of the system. When the desired position is achieved, the splined flexion member's top end is inserted into the adapter 28 and the locking nut 30 is tightened on the adapter 28. Further rotation of the receptacle 12 can be achieved by rotating the entire system 10 at the mandrel 58-housing 62 interface of the installation tool 24. This can be done above the surface prior to insertion of the system 10 into a tubular or wellbore.

The lower body member 18, shown in FIGS. 1 and 12A-12F, has one or more recesses 92 in which are mounted friction members 94 (see FIG. 10A). As shown, the lower body member 18 tapers from top to bottom having a taper surface 93 and a T-shaped groove 96 along its length which holds the connecting bar 15 and guides the movement of the connecting bar 15. A slot 98 in each recess 92 facilitates emplacement of rear ribs 142 of the friction members 94; and screws 99, extending through holes 91 in the friction members 94 and into holes 95 in the lower body member 18, hold the friction members 94 in place. Holes 97 at the top of the lower body member 18 receive shear members for interconnecting the connecting bar 15 and the upper body member 20.

The upper body member 20, shown in FIGS. 1 and FIGS. 11A-11F, tapers from bottom to top and has a taper surface 102 corresponding to the taper surface 93 of the lower body member 18. Thus as the upper body member moves downwardly with respect to the lower body member, the effective largest dimension of the combined body members and connecting bar increases. A groove 104 extends along the length of the upper body member 20 in which is held and in which moves a portion of the connecting bar 15. Shear pins 106 extend through holes 108 in the lower part of the upper body member 20, through the connecting bar 15 and into the holes 97 in the upper part of the lower body member 18. The concave member 22 is pinned to the upper body member 20 with a connecting pin 112 that extends through holes in the concave member 22 and holes in the upper body member 20.

FIGS. 1, and 9A-9C show the connecting bar 15. In certain preferred embodiments, the bar has one or more movable pawls 118 pinioned with a center pin 122 within slots 124 in the bar 15. Springs 126 are partially disposed in spring recesses 127 in the pawls 118. Each spring is biased against an adjacent pawl or an adjacent edge 128 to insure that all the pawls in a series of pawls remain in contact and move together. Edges 128 of each slot 124 acts as a panel stop to prevent further counterclockwise (as viewed in FIG. 9A) rotation of the pawls 118. While the system 10 is run into the casing C, the upper and lower body members are pinned together with the connecting bar 15 pinned between them by the pin 106. The pin 106 extends through hole 108 in the upper body member 20 and hole 97 in the lower body member 18. When the pin 106 holding the upper and lower body members are sheared and relative movement is permitted between the upper and lower body members, the connecting bar 15 guides and controls this movement. As the movement commences, the pawls 118 rest in the slots 124. However, if an upward force is applied to the system 10, pulling the upper body member 20 upwardly, the pawl(s) 118 pivot so that toothed surfaces 132 on one side of some of the pawls engage the lower body member 18 and toothed surfaces 134 on the other side of some of the pawls engage the upper body member (some of the pawls in the middle engaging both body members) thereby preventing upward movement of the upper body member 20 with respect to the lower body member 18. Movement of the middle pawls contacting both body members also forces the two body members apart. This renders the system 10 effectively anchored in the casing C with the lower body member 18 and the upper body member 20 in contact with the casing's interior surface. As shown in FIG. 9C, ends of the pawls 118 will protrude slightly from the bar 15 upon rotation of the pawls in response to an upward force so that the pawls' toothed surfaces can engage the upper and/or lower body members.

In one operation according to this invention, a system 10 according to the present invention is inserted into and through tubing which has been run into casing in a wellbore. The system 10 is at the end of a string as previously described and descends through the tubing, exiting the tubing and entering casing within the wellbore. The system is lowered to a desired point in the casing until the receptacle 12 encounters the anchor 26 and the system 10 is oriented correctly with respect to the anchor's key. Then pushing down on the system 10 shears the pin 106 (e.g. at 2000 pounds force) freeing the upper and lower body members for relative movement. As the upper body member 20 moves downwardly with respect to the lower body member 18, the pin 115 partially disposed in a hole 136, has a protruding portion which moves into contact with a top of the connecting bar 15. The upper body member moving downwardly thus begins to force the connecting bar 15 downwardly. Once the bar 15 reaches a lower limit of its downward travel (at the end of the groove in which the bar moves or due to contact between the upper body member and the casing's interior), further force (e.g. about 500 pounds) on the upper body member 20 shears the pin 115 permitting the upper body member 20 to move further downwardly. As this is occurring, the lower body member 18 is forced sideways in the casing and eventually into frictional contact with the casing's interior (see FIG. 13B). Toothed slips on the lower body member are forced into engagement with the casing's interior with teeth oriented to inhibit upward movement of the lower body member. During movement of the upper body member, the parts of the assembly below the lower body member pivot at the neck of the splined flexion member 14 and at the notch 42 of the tube 16 so that the lower body member 18 pivots to move sideways against the casing's interior. Once the two body members are wedged into place across the casing (see FIG. 13B) (i.e., the system 10 is stabilized so it does not move up or down in the casing or rotate therein), the installation tool 24 is freed from the system 10 by pulling up on the tool 24 with sufficient force to shear the screw 55 (e.g. 12,000 to 15,000 pounds force). Upon removal of the tool 24 and the string to which it is attached, a milling tool may be inserted into the wellbore through the tubing and casing to contact the concave member 22 of the system 10 for a milling operation.

The concave member 22, as shown in FIG. 16, due to the configuration of the hole 112, is free to move upwardly (e.g. about one-half inch in certain embodiments). A toggling connection according to the present invention connects the concave member 22 and the upper body member 20. Initially it is restrained from such movement by a shear pin 133. When an upward pulling force is applied to the system 10 after the upper and lower body members have moved outwardly to wedge against the casing, the shear pin 133 (FIG. 1) is sheared (e.g. at 8,000 pounds force) freeing the concave member 22 to move and to pivot with respect to the upper body member 20. The shear pin 133 extends from a pin hole 165 in the upper body member 20 into a pin hole 167 in the concave member 22. The concave member 22 pivots on the pin 114 which extends through the hole 116 in the upper body member 20 and the hole 112 in the concave member 22. The holes 116 and 112, and 162 and 164, are configured and positioned to allow the concave member 22 to move and to pivot. As shown in FIG. 16, the upper hole 112 of the concave member 22 is elongated providing room for the pin 114 to move therein and the lower half hole 162 which initially encompasses the pin 164 is movable away from the pin 164.

FIGS. 14A-14D illustrate a whipstock system 200 according the present invention which has an inflatable anchor packer 201 with an orientation key 202; a stinger assembly 203 for co-acting with the orientation key 202 to orient the system 200; a tube 221 to interconnect the stinger assembly 203 and an interconnecting link apparatus 205 (one or more connecting links); stabilizing spring bows 204 for centering the tube 221 in a casing C; the link apparatus 205 pivotably linking together the tube 221 and a lower body member 206; the lower body member 206 movably secured to an upper body member 207 by a wedge slide 208; the wedge slide 208 having a T-member 209 movably disposed in a groove 211 in and along the top side of the lower body member 206 and a T-member 210 movably disposed in a groove 212 in and along the top side of the upper body member 207; a concave member 213 hingedly connected to the upper body member 207 with a pin 214; and a setting tool 215 secured to the concave with a shear stud 216. A shear pin 217 secures the upper body member 207 to the wedge slide 208 and a shear pin 218 secures the lower body member to the wedge slide 208.

As shown in FIG. 14A, the system 200 has been inserted through a casing S which has a smaller diameter than the casing C. The shear pins 217 and 218 have not been sheared so the upper and lower body members 207, 206 have not moved with respect to each other. As shown in FIG. 14B, downward force has been applied through the setting tool 215 shearing the shear pins 217, 218 and moving the upper body member downwardly and sideways to contact the interior of the casing C. Further downward force on the setting tool 215 has pushed the lower body member against the casing's interior (FIG. 14C) and a toothed slip 219 has engaged the casing's interior. Also, the force on the shear stud 216 has been sufficient to shear it and free the setting tool 215 which, as shown in FIG. 14C, has been removed. The lower body member 206 has pivoted on the link apparatus 205 and moved to engage the casing. The concave member 213 has pivoted at the hinge pin 214 to fall back against the casing's interior. An appropriate mill or other tool can now be inserted into the casing to engage the concave member 213. A packer 220 isolates the two casings.

FIG. 15 illustrates a system 250 according to the present invention which is similar to that of FIG. 14 and similar parts have similar numeral indicators. The link apparatus 205 (one or more connecting links) interconnects the tube 221 with a lower body member 226 having a toothed slip 229. An upper body member 227 with a toothed friction member 231 is pivotably connected to the lower body member 226 by link apparatus 228 (one or more connecting links; plural links disposed opposite each other) and a concave member 232 is formed integrally of the upper body member 227. The system 250 may include the other items shown in FIG. 14A and operates in a similar manner with the link apparatus 228 serving to control and guide upper and lower body member movement.

In conclusion, therefore, it is seen that the present invention and the embodiments disclosed herein and those covered by the appended claims are well adapted to carry out the objectives and obtain the ends set forth. Certain changes can be made in the subject matter described, shown and claimed without departing from the spirit and the scope of this invention. It is realized that changes are possible within the scope of this invention and it is further intended that each element or step recited in any of the following claims is to be understood as referring to all equivalent elements or steps. The following claims are intended to cover the invention as broadly as legally possible in whatever form its principles may be utilized.

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Classifications
U.S. Classification166/117.6, 175/81
International ClassificationE21B23/01, E21B23/02, E21B23/00, E21B10/60, E21B49/06, E21B7/06, E21B7/08, E21B29/06, E21B12/04, E21B10/50
Cooperative ClassificationE21B23/00, E21B10/50, E21B29/06, E21B10/60, E21B12/04, E21B7/061, E21B23/01, E21B23/02
European ClassificationE21B29/06, E21B10/60, E21B10/50, E21B7/06B, E21B23/01, E21B12/04, E21B23/00, E21B49/06, E21B23/02
Legal Events
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Mar 5, 1999FPAYFee payment
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Sep 10, 1993ASAssignment
Owner name: WEATHERFORD U.S., INC., TEXAS
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Effective date: 19930909
Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNOR:SCHNITKER, MARK W.;REEL/FRAME:006693/0887